Heres a tip to get the 3" under string length on em.
61" for a 64" ntn.
I lay out the nocks on the bow back, 32" each way from center for a 64".
Then make a 45* mark on limb edge, and file on the side of line toward center, leaving the mark.
When finishing grooves, I round the belly side of the nock so the string curves into nock, not a sharp corner. Much nicer to your string.
If you use this formula, a 61" string (actual) will fit the 64" bow with a bout a 6.75" brace.
Sweet looking bow Stacy!!